protein extraction for use in ELISA - Post Any Protocol, Method, Technique, Procedure or Tips / Troubleshooting for any Molecular Biology Technique.

I am hoping for some suggestions for a protein that I am trying to extract for detection in an ELISA.

I have a protein that is 22 kDa which is soluble in sodium borate at either a low pH (<4) or high pH (>9). In its pure form I can detects it in a ELISA when using specific antibodies. When the protein is in commercial fish feeds I can not longer detect it.
Has any one got an extraction method that I could try?

Try separating your protein of interest with [Only registered users see links. ]. Then cut the bands from the gel and extract the protein with either electroelution using a [Only registered users see links. ] or digest the protein using an [Only registered users see links. ].

If you still have trouble with your sample after SDS PAGE followed by electroelution or in-gel digestion, try cleaning up the sample with a C8 reversed phase product. I use [Only registered users see links. ]. Hope this helps, good luck.